Method for providing subscriber-based ringback tone in flexible paging mode

ABSTRACT

The present invention provides a caller with an arbitrary sound chosen by a called subscriber instead of a conventional RBT (RingBack Tone) without fails even in a flexible paging mode. In the present method: both exchangers check individually whether first information on replacing RBT or not and second information informing a route to a sound providing means have been stored for a called terminal, when an originating exchanger requests a trunk connection to said both exchangers according to a flexible paging procedure, and receive the first and the second information from a home location register after requesting if said information has not been stored, and request individually a trunk connection to the sound providing means while furnishing information identifying the called, based on the already-stored or the received first and the second information; and the originating exchanger selects one of the two paths connected to said both exchangers, and delivers to a caller an RBT replacing sound determined by the sound providing means that is received through the selected path.

CROSS REFERENCE TO RELATED APPLICATION

This application is the National Phase application of InternationalApplication No. PCT/KR2003/001564, filed Aug. 4, 2003, which designatesthe United States and was published in English. This application, in itsentirety, is incorporated herein by reference.

1. TECHNICAL FIELD

The present invention relates to method for providing an arbitrary soundchosen by a called subscriber for a calling subscriber instead of aconventional ringback tone without fails even in case that a flexiblepaging is conducted.

2. BACKGROUND ART

When a subscriber calls another through a mobile communication network,a terminating exchanger on the network provides the caller with auniform ringback tone.

Since the ringback tone is same all the time, a caller can not identifya called before the called answers. Furthermore, the uniform ringbacktone can not satisfy various subscribers' needs to reveal theirindividuality.

By the way, various ad methods are being proposed in these days. One ofthese ad methods is to send an ad sound message to a caller instead of aconventional ringback tone. However, such an ad sound message is chosenunilaterally by a network operating enterprise. If a caller heard such aunilateral ad sound he or she could talk over a mobile telephone with acalled for a limited time.

However, the method that an ad sound is provided instead of aconventional common ringback tone still has the aforementioneddrawbacks. That is, a caller can not identify a called before the calledanswers and the uniform ringback tone cannot satisfy varioussubscribers' needs to reveal their individuality.

3. DISCLOSURE OF INVENTION

It is an object of the present invention to provide a method forfurnishing a caller with an arbitrary sound chosen or registered by acalled subscriber instead of a conventional RBT (RingBack Tone). In thepresent method, an arbitrary RBT-replacing sound chosen or registered bya subscriber is stored in a server separated from mobile exchangersfirst, and if a certain subscriber is called, a terminating exchangerfor the call receives from the server an RBT-replacing sound that isassigned to the called, and then provides the received sound for acaller instead of a conventional RBT.

It is another object of the present invention to provide a method forfurnishing a caller with an arbitrary sound chosen or registered by acalled subscriber instead of a conventional RBT without fails even incase that a flexible paging is conducted for a called subscriber who isin or moves fast an overlapped service zone.

A method of providing an arbitrary sound as an RBT in a communicationnetwork where flexible paging is conducted for a called terminal inaccordance with the present invention is characterized in that itcomprises: a first step, conducted respectively by both exchangers, ofchecking whether first information on replacing RBT or not and secondinformation informing a route to a sound providing means have beenstored for the called terminal, when an originating exchanger requests atrunk connection to said both exchangers according to a flexible pagingprocedure, and receiving the first and the second information from anHLR (Home Location Register) after requesting if said information hasnot been stored, and requesting a trunk connection to the soundproviding means while furnishing information identifying the called,based on the already-stored or the received first and the secondinformation; a second step, conducted by the sound providing means, ofdetermining an RBT-replacing sound based on the called-identifyinginformation, and transmitting the determined RBT-replacing sound to theoriginating exchanger through two paths made respectively by way of saidboth exchangers; and a third step, conducted by the originatingexchanger, of selecting one path of the two, and delivering thedetermined RBT replacing sound received through the selected path to acaller.

A method of processing location registration in an HLR to provide anarbitrary sound as an RBT in a communication network where flexiblepaging is conducted for a called terminal in accordance with the presentinvention is characterized in that it comprises the steps of: furnishinga first exchanger with first information on whether or not RBT is to bereplaced for a terminal and second information informing a route to asound providing means, when location of the terminal is registeredthrough the first exchanger, and retaining a second exchanger asprevious location of the terminal, the second exchanger having servedthe terminal just before; requesting routing information to the firstand the second exchanger based on the registered and the retainedlocation information of the terminal when location request for theterminal is received from an originating exchanger, and providing thefirst and the second information for the second exchanger; anddelivering all of routing information received, in response to therouting information request, from the first and the second exchanger tothe originating exchanger as a response to the location request.

Another method of processing location registration in an HLR to providean arbitrary sound as an RBT in a communication network where flexiblepaging is conducted for a called terminal in accordance with the presentinvention is characterized in that it comprises the steps of: retaininga second exchanger as previous location of a terminal when location ofthe terminal is registered through a first exchanger, the secondexchanger having served the terminal just before; requesting routinginformation to the first and the second exchanger based on theregistered and the retained location information of the terminal when alocation request for the terminal is received from an originatingexchanger, and providing both of the first and the second exchanger withfirst information on whether or not an RBT is to be replaced for theterminal and second information informing a route to a sound providingmeans; and delivering all of routing information received, in responseto the routing information request, from the first and the secondexchangers to the originating exchanger as a response to the locationrequest.

Another method of providing an arbitrary sound as an RBT in acommunication network where flexible paging is conducted for a calledterminal in accordance with the present invention is characterized inthat it comprises: a first step, conducted by an HLR, of furnishing afirst exchanger and a second one with first information on whether ornot an RBT is to be replaced for a terminal and second informationinforming a route to a sound providing means, when location of theterminal is registered through the first exchanger, wherein the secondexchanger is registered as previous location of the terminal; a secondstep conducted respectively by the first and the second exchanger whichare individually requested by an originating exchanger to make a trunkconnection to the originating exchanger according to a flexible pagingprocedure, of requesting the sound providing means to make a trunkconnection therebetween while furnishing information identifying theterminal that is called by a subscriber, based on the first and thesecond information furnished from the HLR; a third step, conducted bythe sound providing means, of determining an RBT-replacing sound basedon the terminal-identifying information, and transmitting the determinedRBT-replacing sound to the originating exchanger through two paths maderespectively by way of said both exchangers; and a fourth step,conducted by the originating exchanger, of selecting one path of thetwo, and delivering the determined RBT replacing sound received throughthe selected path to the subscriber.

The above-characterized method provides a personal ad way by allowing aregistered personal introducing or identifying sound to be used insteadof an RBT. In addition, a caller is able to know by only hearing anRBT-replacing sound whether he or she called rightly. An enterprise aswell as individual persons can advertise efficiently through registeringan RBT-replacing sound.

Especially, an RBT-replacing sound is provided for a caller withoutfails even when a flexible paging is conducted.

4. BRIEF DESCRIPTION OF DRAWINGS

In the drawings:

FIG. 1 is a procedure chart of an embodiment of a subscriber-basedRBT-replacing sound providing service in accordance with the presentinvention;

FIG. 2 is a procedure chart of a flexible paging that has been proposedby this applicant;

FIG. 3 is a simplified diagram of a mobile communication network which asubscriber-based RBT-replacing sound providing method is embedded in;

FIG. 4 is a procedure chart to subscribe to a subscriber-basedRBT-replacing sound providing service in accordance with the presentinvention;

FIG. 5 is a procedure chart to change/add an RBT sound to be used inRBT-replacing sound providing service in accordance with the presentinvention;

FIG. 6 is a procedure chart to terminate a subscriber-basedRBT-replacing sound providing service in accordance with the presentinvention;

FIG. 7 is a procedure chart of an embodiment to provide asubscriber-based RBT replacing service in case of flexible paging inaccordance with the present invention;

FIG. 8 is a procedure chart of another embodiment to provide asubscriber-based RBT replacing service in case of flexible paging inaccordance with the present invention; and

FIG. 9 shows format of the value-added service parameters including anRBT-replacing service field that are delivered from an HLR to acall-terminating exchanger.

5. MODES FOR CARRYING OUT THE INVENTION

In order that the invention may be fully understood, a preferredembodiment thereof will now be described with reference to theaccompanying drawings.

FIG. 1 is a procedure chart of conducting a subscriber-basedRBT-replacing sound providing service in accordance with the presentinvention. The procedure of FIG. 1 is conducted through a mobilecommunication network structured as FIG. 3.

The network of FIG. 3 includes an HLR (Home Location Register) 10;mobile exchangers 31, 32 and 33 (also called ‘MSC’ (Mobile SwitchingCenter)) being capable of communicating with the HLR 10 via a No. 7signaling network 20 based on No. 7 signaling transfer protocol; a soundstorager 50, connected to the No. 7 signaling network 20 via a gateway40, storing RBT-replacing sounds and communicating with the exchangers31, 32 and 33; an SSMS (Sound Storager Managing Server) 70, connected tothe sound storager 50 via Internet 60, controlling management ofRBT-replacing sounds in the sound storager 50; a subscriber db 80connected to the HLR 10 via Internet 60; and a web server 100, connectedto Internet 60 via a gateway 90, communicating with the sound storager50 and the SSMS 70.

The HLR 10 functions as a conventional network element and it has inevery subscriber profile the first information on whether or not an RBTis to be replaced and the second information informing a route to thesound storager 50. The first and the second information are written inthe value-added service parameters of each subscriber profile.

Furthermore, when location registration of a mobile terminal is changedfrom an exchanger to another, the HLR 10 stores identification of acurrent serving exchanger, which the terminal has just registered to,while retaining identification of a previous serving exchanger. Thereason not to delete identification of the previous serving exchanger isfor conducting flexible paging.

The HLR 10 can send the above-mentioned first and the second informationthrough a routing request message (e.g., a message sent at the step S102in FIG. 1) to a call-terminating exchanger 32 or 33. The routing requestmessage is sent in order to set up a trunk connection between acall-originating exchanger and a call-terminating one.

Either of the mobile exchangers 31 and 32 functioning as conventionalnetwork elements receives the first and the second information of asubscriber through communicating with the HLR 10 when the subscriberrequests location registration. If the location-registered subscriber iscalled, the exchanger 31 or 32 receives an RBT-replacing sound from thesound storager 50 based on the received first and second information,and then provides a caller with the received RBT-replacing sound.

Furthermore, either of the exchangers 31 and 32 searches its local db,namely, VLR (Visitor Location Register) for the first and the secondinformation of a called terminal before making a call to the terminal.If it has not the first and the second information, it requests the HLR10 to download that information.

The sound storager 50 stores a plurality of digital sounds to be usedfor replacing an RBT. The stored digital sounds are provided for theexchangers 31 and 32 via the gateway 40.

The SSMS 70 communicates with the sound storager 50 via Internet 60 andit chooses a digital sound based on information written in an RBTservice table. A unique code to identify the chosen digital sound isnotified the sound storager 50 in order that a stored sound identifiedby the code is sent to the exchanger 31 or 32 from the sound storager50. The RBT service table used for choice of a digital sound allocatedfor each subscriber includes several codes linked to caller's personalinformation, caller or caller-group identifying information, and/or calltime zone. Therefore, a digital sound can be chosen by the SSMS 70 basedon who calls, which group a caller belongs to, age, sex, or occupationof a caller, and/or when a subscriber is called.

Information in the RBT service table is determined when a personsubscribes to the value-added service and is then modified by his or herrequest.

The web server 100, connected to the sound storager 50 and/or the SSMS70 via Internet 60, adds digital sounds to the sound storager 50 andconducts operations to update or change contents of the RBT servicetable and codes, if necessary, related digital sounds for the SSMS 70.The updating or changing operation is initiated by subscriber's requestthrough web pages of the web server 100.

The RBT sound providing procedure depicted in FIG. 1 conducted throughthe network of FIG. 3 is described in detail below.

If an arbitrary subscriber within a service zone of the exchanger 31calls another subscriber within the exchanger 32 who has subscribed tothe RBT replacement service, the originating exchanger 31 sends alocation request message to the HLR 10 to inquire where the called is(S101). Then, the HLR 10 sends a routing request message to theterminating exchanger 32 (S102), and the terminating exchanger 32informs the HLR 10 of routing information, e.g., TLDN (Temporary LocalDirectory Number) in response to the routing request message (S103).

The HLR 10 delivers the routing information to the originating exchanger31 in response to the inquiry step S101 (S104). The originatingexchanger 31 requests the terminating exchange 32 based on the routinginformation to make a trunk connection therebetween (S105). The call fortrunk connection is called ‘ISUP’ in common.

In the meantime, the terminating exchanger 32 checks the informationrelated with the present RBT-replacing service (e.g., ‘SRBT’ field ofFIG. 9 that was registered for the called in its local db at the stepS408-2 in the procedure of FIG. 4) to know if the RBT-replacing servicefor the called is ‘in-service’ and ‘activated’ as well. If then, theterminating exchanger 32 makes a trunk connection (ISUP) to the soundstorager 50 with reference to the routing information that was alsoreceived and stored at the step S408-2 in the procedure of FIG. 4. Atthis time, mobile telephone numbers of the caller and the called aresent to the sound storager 50 (S106). While the above processes areconducted, a conventional common RBT is not transmitted to theoriginating exchanger 31.

Now, respective trunk connections are made between the originatingexchanger 31 and the terminating one 32 and between the terminatingexchanger 32 and the sound storager 50.

The information related with RBT-replacing service is provided (at thestep S408-2 in the procedure of FIG. 4) from the HLR 10 to a servingexchanger, which a terminal has registered to, through a responsemessage to location registration request ‘Registration Notification’from the serving exchanger.

The sound storager 50 asks an adequate code to the SSMS 70 whileproviding the received numbers for the SSMS 70 (S107). The SSMS 70examines an RBT service table allocated for the called number todetermine a code matched with the calling number (if received), andinforms the sound storager 50 of the determined code (S108) in responseto the code-requesting step S107. The sound storager 50 transmits anRBT-replacing sound corresponding to the determined code to the callerthrough the trunk connections between the sound storager 50 and theterminating exchanger 32 and between the terminating exchanger 32 andthe originating one 31 (S109).

If the called answers call arrival from the terminating exchanger 32while the determined RBT-replacing sound is being transmitted instead ofa conventional RBT, the terminating exchanger 32 requests the soundstorager 50 to release the established trunk connection (S110). Then,voice or data are communicated between the caller and the called throughthe trunk connection between the originating 31 and the terminatingexchanger 32 (S111).

The HLR 10 stores an identification, e.g., TLDN or accessing address ofa currently serving exchanger, which a terminal has been registered to,in order to deliver a call to the terminal if called.

By the way, if the terminal frequently changes its location between theserving exchanger and a neighboring exchanger while crossing anoverlapped zone of the respective coverage of the two exchangers,registration/cancellation processes are conducted among the HLR 10 andboth of the exchangers as frequently as the location changes. Suchfrequent processes cause undesirable burden to a communication network.

Therefore, a location updating threshold time is used in the HLR 10 foralleviating such a load. Location of a terminal registered in the HLR 10is not updated within the threshold time after registration of the sameterminal.

Consequently, actual location of a terminal is not registeredimmediately in the HLR 10, which leads to difference between the actuallocation of the terminal and registered location information, namely,exchanger identification stored in the HLR 10. If the terminal is calledunder this situation, the HLR 10 may send a routing request message towrong exchanger which is regarded a right one by the HLR 10 since theterminal is probably out of a coverage of the exchanger.

To solve this problem, a flexible paging method depicted in FIG. 2 hasbeen proposed by the present applicant. The flexible paging method isbriefly explained below.

In case that a terminal moves into a coverage of the second exchanger 33(S202) after it is registered to the first exchanger 32 in the HLR 10(S201), the HLR 10 updates current location information from the firstexchanger 32 to the second 33 while retaining identification, e.g.,accessing address of the first 32 as previous location information. Thatis, location information for both exchangers is preserved for theterminal in the HLR 10 (S203).

If another terminal within a coverage of an exchanger 31 calls theterminal, the originating exchanger 31 sends the HLR 10 a locationrequest message ‘LOCREQ’ asking where the called terminal is (S204).

Then, the HLR 10 sends, based on the location information, acall-routing request message ‘ROUREQ’ to the first exchanger 32(S205-1), which is previous location of the called terminal, as well asthe second exchanger 33 (S205-2) which is regarded current location.Thus, both exchangers 32 and 33 send routing information directed tothemselves, TLDN1 and TLDN2 to the HLR 10 respectively in response tothe message ‘LOCREQ’ (S206-1, S206-2).

The HLR 10 delivers the received routing information, e.g., TLDN1 andTLDN2 to the originating exchanger 31 in response to the step S204(S207). Then, the originating exchanger 31 makes dual trunk connectionsto both of the exchangers 32 and 33 simultaneously (S208-1, S208-2)based on the received routing information.

If dual trunk connections are made, the first exchanger 32 and thesecond 33 send a common RBT respectively to the calling terminal (notshown) through the originating exchanger 31. At the same time, both ofthe exchangers 32 and 33 transmit a paging signal (S209-1, S209-2).

If the called, which is moving here and there in an overlapped servicezone between the exchangers 32 and 33, answers the paging signal fromthe first terminating exchanger 32 first (S210), the originatingexchanger 31, acknowledging the call answer from the first terminatingexchanger 32, releases the trunk connection to the second terminatingexchanger 33 to sustain only one connection to the first 32, which willbe used for data or voice communication between the caller and thecalled (S211).

By the way, information related with RBT replacing service is downloadedto an exchanger, which a certain subscriber is registered to, through aresponse message to location registration request as explained in theembodiment of RBT replacing service depicted in FIG. 1. Therefore, inthe above-explained flexible paging, only one of both exchangers 32 and33 has the information related with RBT replacing service in the eventthat the called has been subscribed to RBT replacing service.

Therefore, in the embodiment of FIG. 1, if the called responds thepaging from the first terminating exchanger 32 first in the event thatthe second exchanger 33 is lately registered for the called in the HLR10, an RBT replacing sound can not be provided for the calling terminalbecause not the first 32 but the second exchanger 33 has RBT servicerelated information. That is, the first terminating exchanger 32, whichhas not RBT service related information for the called, can not make atrunk call to the sound storager 50, so that it can not obtain a certainsound to replace a common RBT.

The above subscriber-based RBT sound providing service can besubstantially embodied through the mobile communication network of FIG.3 as follows.

When a subscriber applies for subscription to the value-added service ofRBT replacement all information included in the application is stored inthe subscriber db 80 that requests registration of RBT replacementservice to the HLR 10. Then, the HLR 10 writes necessary information invalue-added service parameters of that subscriber.

Afterwards, if location registration for that subscriber is requestedfrom a serving exchanger 31 or 32, e.g., the exchanger 32 the HLR 10provides RBT service-related information and routing information for theexchanger 32 that requested location registration. The routinginformation is needed to make a trunk connection to the sound storager50. The exchanger 32 registers the received information for thatsubscriber in a local subscriber db.

If an arbitrary subscriber at the exchanger 31 calls thelocation-registered subscriber, a trunk connection ‘ISUP’ is madebetween the originating 31 and the terminating exchanger 32 afterrouting information exchange through the HLR 10. After a trunkconnection is setup, the terminating exchanger 32, knowing based on theregistered information of the called subscriber that RBT replacementservice is ON, makes another trunk connection to the sound storager 50addressed by the registered information. At the same time, theterminating exchanger 32 provides the sound storager 50 with informationof the called subscriber, e.g., mobile telephone number and starts topage the called.

The sound storager 50 inquires of the SSMS 70 about which digital soundis set now for the called subscriber. Then, the SSMS 70 informs thesound storager 50 of a code for digital sound having been chosen for agiven condition by the called.

The sound storager 50 sends a digital sound identified by the receivedcode to the originating exchanger 31 through the setup trunk connectionbetween the two exchangers 31 and 32. The originating exchanger 31transmits the digital sound from the sound storager 50 to the calleruntil the called answers the call. Thus, the caller can hear the digitalsound instead of a conventional RBT during the paging. The moment thecalled answers the paging, the terminating exchanger 32 releases thetrunk connection established to the sound storager 50. The conversationbetween the caller and the called is communicated through the trunkconnection made between the originating 31 and the terminating exchanger32.

FIG. 4 is a procedure chart to subscribe to a subscriber-basedRBT-replacing sound providing service in accordance with the presentinvention.

If subscription to the RBT-replacement service is asked (S401),subscription information including mobile telephone number of thesubscriber is stored in the subscriber db 80 first and is then deliveredto the HLR 10 (S402). The HLR 10 updates service information of thesubscriber profile to indicate that the subscriber has subscribed to RBTreplacement service (S403).

In addition, the subscriber db 80 also sends the subscriptioninformation including a chosen digital sound and mobile telephone numberto the SSMS 70 (S404). The SSMS 70 writes a code associated with thechosen digital sound in an RBT service table allocated for that mobiletelephone number (S405).

If the received subscription information includes particulars of soundassignments, namely if the received subscription information assignsdifferent digital sounds for each caller, each caller group, and/or eachtime zone, the SSMS 70 writes different codes of the respective digitalsounds in each condition field of the RBT service table, at the stepS405.

Afterwards, if location registration for the subscriber is requestedfrom the exchanger 32 to the HLR 10 (S406), the HLR 10 checks profile ofthe subscriber to know whether the subscriber has been subscribed to theRBT replacement service (S407). If not subscribed, the HLR 10 sends anordinary response message to the location registration request to theexchanger 32 as in the conventional request processing procedure(S408-1). However, if subscribed, the HLR 10 sends the exchanger 32 aresponse message including RBT service-related information and routinginformation, e.g., routing digits to direct to the sound storager 50.The exchanger 32 registers the received information in the subscriber'sprofile on a local db, e.g., a VLR (Visitor Location Register) (S408-2).

The RET service-related information can be carried by an SRBT (SpecificRBT) field, which was defined as a ‘reserve’ field before, of thevalue-added service parameters ‘CallingFeaturesIndicator2’ shown in FIG.9. The 2-bit SRBT field is set to ‘10’ in case that the RBT replacementservice is not activated even though that service is valid bysubscription, and it is set to ‘11’ in case that the RBT replacementservice is in active state. A message including the parameters‘CallingFeaturesIndicator2’ responsive to the location registrationrequest is delivered from the HLR 10 to the exchanger 32.

The service information parameters ‘CallingFeaturesIndicator2’ of FIG. 9are composed of a VMSB field indicative of state of voice mail servicebusy; a VMSU field indicative of state of voice mail service busyunconditional; a VMSNA field indicative of state of voice mail servicebusy no answer; an FMSNA field indicative of state of fax mail serviceno answer; an FMSB field indicative of state of fax mail service busy;an FMSU field indicative of state of fax mail service unconditional; anMC field indicative of multi-call; a CC field indicative of conferencecall; an MUDN field indicative of multiple unit directory number; andothers.

After the step S408-2 is completed, the HLR 10, as shown in FIG. 4, mayconduct additional following steps.

The HLR 10 checks whether a flexible paging mode is set or not (S409).If flexible paging mode, the HLR 10 also sends the RBT service-relatedinformation including RBT service setting information and routinginformation to a previously-serving exchanger 33 (S410), based onlocation information of both exchangers, namely, the current servingexchanger 32, which the subscriber has just registered to, and theprevious serving exchanger 33. At this time, the RBT service-relatedinformation can be provided for the exchanger 33, that is regardednot-serving exchanger, through a newly-defined message that is not aresponse message to location registration request one.

The steps S406 to S408-2 are preferable in the RBT replacing service,however, those steps may be selectively used in consideration of otherprocedures adopted in different embodiments which will be describedlater. In addition, the steps S409 to S410 are also selectively used inconsideration of other procedures adopted in different embodiments whichwill be described later. However, these steps need to define a newmessage format, so that other embodiments depicted in FIGS. 7 and 8,which need not the two steps S409 and S410, are more preferable.

FIG. 5 is a procedure chart to change/add an RBT sound to be used inRBT-replacing sound providing service in accordance with the presentinvention.

A subscriber, who has subscribed to the RBT replacement serviceaccording to the above-explained procedure of FIG. 4, connects his orher personal computer to the web server 100, first. Then, the web server100 provides web pages on the connected computer screen to enable thesubscriber to change/add information about RBT replacement service.

The subscriber enters mobile telephone number through an adequate webpage and then selects a desired RBT-replacing sound from a list showingall or a part of sounds stored in the sound storager 50. If thesubscriber requests change of RBT-replacing sound to the chosen one(S501), the web server 100 sends a change-requesting message to the SSMS70 (S502). The SSMS 70 changes the current code with another codeassigned to the chosen RBT-replacing sound in an RBT service tableallocated for the entered mobile telephone number (S503). Afterwards, anRBT-replacing sound identified by the changed code will be providedinstead of a conventional RBT.

If the subscriber selects to add a new RET-replacing sound on a webpage, the SSMS 70 provides an input web page. Then, the subscriberenters his or her mobile telephone number in the input web page anduploads a sound file including voice, sound logo, or music through theinput web page (S504). The web server 100 requests the sound storager 50to add a new RBT-replacing sound by delivering the inputted data to thesound storager 50 (S505). The sound storager 50 registers the uploadedsound file as a new RBT-replacing sound (S506) and requests the SSMS 70to assign a new code to the registered RBT-replacing sound (S507). TheSSMS 70 informs the sound storager 50 of the newly-assigned code andchanges the current code with the newly-assigned code in an RBT servicetable allocated for the subscriber.

FIG. 6 is a procedure chart to terminate a subscriber-basedRBT-replacing sound providing service in accordance with the presentinvention.

If termination of RBT replacement service is asked from a subscriber(S601), the subscriber db 80 deletes subscription information for RBTreplacement service associated with the subscriber, namely, thesubscriber's telephone number, and sends service terminating informationincluding a mobile telephone number to the HLR 10 (S602). The HLR 10alters service information of the subscriber's profile to indicate thatthe subscriber has not subscribed to RBT replacement service (S603).

The subscriber db 80 also sends the service terminating information tothe SSMS 70 (S604), then the SSMS 70 deletes a current code, allocatedat the step S305, in an RBT service table for the subscriber based onthe received service terminating information (S605).

FIG. 7 is a procedure chart of another embodiment of the presentinvention to conduct a subscriber-based RBT-replacing sound providingservice after completion of the procedure of FIG. 4 and/or 5. Thisembodiment always has an RBT replacing sound provided for a caller evenin case of flexible paging.

In addition, for the embodiment given in FIG. 7, the steps S406 to S408in the RBT replacement service subscribing procedure of FIG. 4 have beenconducted, however, the steps S409 and S410 have not been conducted.

If an arbitrary subscriber within a service zone of the exchanger 31calls another subscriber, who has subscribed to the RBT replacementservice, within the exchanger 32, the originating exchanger 31 sends alocation request message to the HLR 10 to inquire where the called is(S701).

Then, the HLR 10 sends a routing request message to both of the firstterminating exchanger 32 and the second 33 simultaneously (S702-1,S702-2) based on previous and current location information for flexiblepaging that has been retained by the step S203 in the procedure of FIG.2. It is assumed that the first exchanger 32 is a current serving onethat is lately registered for the called subscriber in the HLR 10 andthat the second exchanger 33 is a previously serving one. Both of theexchangers 32 and 33 send individual routing information, e.g., TLDN1and TLDN 2 to the HLR 10 in response to the routing request message(S703-1, S703-2).

The HLR 10 delivers all the routing information TLDN1 and TLDN2 fromboth exchangers 32 and 33 to the originating exchanger 31 in response tothe inquiry step S701 (S704). Then, the originating exchanger 31requests, based on the received routing information, both of the firstterminating exchange 32 and the second 33 to make dual trunk connectionsto the first exchanger 32 and the second 33 (S705-1, S705-2).

In the meantime, the first terminating exchanger 32 checks whether ornot it has RBT service-related information for the called (S706). In theabove assumption, since the first terminating exchanger 32 is registeredlately in the HLR 10 the RBT service-related information including RBTservice setting information, e.g., SRBT field shown in FIG. 9 for thecalled has been already delivered to the first exchanger 32 at the step408-2 in the procedure of FIG. 4. If the two bits of the received ‘SRBT’field are ‘11’ which means ‘in-service’ and ‘activated’, the firstterminating exchanger 32 makes a trunk connection to the sound storager50, which is assigned to the called subscriber, with reference to therouting information included in the RBT service-related information thathas been received and stored at the step S408-2. At this time, mobiletelephone numbers of the caller and the called are sent to the soundstorager 50 (S707). While the above processes are conducted, aconventional RBT is not transmitted to the originating exchanger 31.

In the meantime, the second exchanger 33 also checks whether or not ithas RBT service-related information for the called (S708). If it had, itcould make a trunk connection to the sound storager 50 the same as thefirst exchanger 32. However, it has not the RBT service-relatedinformation for the called or has deleted, so that it requests RBTservice-related information for the called to the HLR 10 (S709) andstores in its local db if received (S710). And, the second exchanger 33makes a trunk connection to the sound storager 50 with reference to thereceived RBT service-related information as the step S707. At this time,mobile telephone numbers of the caller and the called are sent to thesound storager 50 (S711).

Now, dual paths are made between the originating exchanger 31 and thesound storager 50 via the first terminating exchanger 32 and between theoriginating exchanger 31 and the sound storager 50 via the secondterminating exchanger 33.

Each time the sound storager 50 receives calling and/or called number itasks an adequate code to the SSMS 70 while providing the received numberfor the SSMS 70 (S712-1, S712-2). The SSMS 70 examines an RBT servicetable allocated for the called number to determine a code matched withthe calling number (if received), and informs the sound storager 50 ofthe determined code twice (S713-1, S713-2) in response to thecode-requesting steps S712-1 and S712-2.

The sound storager 50 transmits an RBT-replacing sound corresponding tothe determined code to the originating exchanger 31 through the dualtrunk connections made to the first terminating exchanger 32 and to thesecond 33. Then, the originating exchanger 31 selects one trunkconnection of the two that is made to the exchanger 32 or 33 thatresponded first to the ISUP requests of the steps S705-1 and S705-2, anddelivers an RBT replacing sound received through the selected trunkconnection to the caller (S714).

If the called answers paging of either of both terminating exchangers 32and 33 (S715) while the determined RBT-replacing sound is beingtransmitted instead of a conventional RBT, the originating exchanger 31,that is informed of the call answer by either exchanger 32 or 33,requests the other exchanger, whose paging is not answered, to releasethe established trunk connection (S716). In this embodiment, it isassumed that the called answers the call paging from the firstterminating exchanger 32, so that the trunk connection made to the firstterminating exchanger 32 is maintained while the other trunk connectionto the second exchanger 33 is released.

Afterwards, the first terminating exchanger 32, based on the callanswer, requests the sound storager 50 to release the established trunkconnection (S717-1) and the second terminating exchanger 33, based onthe request of ISUP release from the originating exchanger 31, requeststhe sound storager 50 to release the established trunk connection(S717-2). At the same time, voice or data are communicated between thecaller and the called through the trunk connection between theoriginating 31 and the first terminating exchanger 32 (S718).

FIG. 8 is a procedure chart of another embodiment of the presentinvention to conduct a subscriber-based RBT-replacing sound providingservice after completion of the procedure of FIG. 4 and/or 5. Thisembodiment also has an RBT replacing sound provided for a caller even incase of flexible paging.

In addition, for the embodiment given in FIG. 8, the steps S406 to S408in the RBT replacement service subscribing procedure of FIG. 4 have beenconducted, however, the steps S409 and S410 have not.

If an arbitrary subscriber within a service zone of the exchanger 31calls another subscriber, who has subscribed to the RBT replacementservice, within the exchanger 32, the originating exchanger 31 sends alocation request message to the HLR 10 to inquire where the called is(S801).

Then, the HLR 10 sends a routing request message to both of the firstterminating exchanger 32 and the second 33 simultaneously based onprevious and current location information for flexible paging that hasbeen retained by the step S203 in the procedure of FIG. 2. If it isassumed that the first exchanger 32 is a current serving one that islately registered for the called subscriber in the HLR 10 and that thesecond exchanger 33 is a previously serving one, the HLR 10 knows thatit has already sent RBT service-related information to the firstterminating exchanger 32 when location registration of the called isconducted. Therefore, the HLR 10 sends an ordinary routing requestmessage to the first terminating exchanger 32 (S802-1) while sending thesecond terminating exchanger 33 a special routing request message(S802-2) that includes RBT service-related information for the called.

Accordingly, both of the exchangers 32 and 33 send routing information,e.g., TLDN1 and TLDN 2 to the HLR 10 in response to the individualrouting request messages of the steps S802-1 and S802-2 (S803-1,S803-2).

The HLR 10 delivers all the routing information TLDN1 and TLDN2 fromboth exchangers 32 and 33 to the originating exchanger 31 in response tothe inquiry step S801 (S804). Then, the originating exchanger 31requests, based on the received routing information, both of the firstterminating exchange 32 and the second 33 to make dual trunk connectionsto the first exchanger 32 and the second 33 (S805-1, S805-2).

The first terminating exchanger 32 makes a trunk connection to the soundstorager 50, that is assigned to the called subscriber, with referenceto the routing information included in RBT service-related information(S806-1) that has been received and stored at the step S408-2 while thesecond terminating exchanger 33 does the same (S806-2) with reference toRBT service-related information that is received at the step S802-2. Ateach trunk connection requesting step, mobile telephone numbers of thecaller and the called are sent to the sound storager 50.

Now, dual paths are made between the originating exchanger 31 and thesound storager 50 via the first terminating exchanger 32 and between theoriginating exchanger 31 and the sound storager 50 via the secondterminating exchanger 33.

Each time the sound storager 50 receives calling and/or called number itasks an adequate code to the SSMS 70 while providing the received numberfor the SSMS 70 (S5807-1, S807-2). The SSMS 70 examines an RBT servicetable allocated for the called number to determine a code matched withthe calling number (if received), and informs the sound storager 50 ofthe determined code twice (S808-1, S808-2) in response to thecode-requesting steps S807-1 and S807-2.

The sound storager 50 transmits an RBT-replacing sound corresponding tothe determined code to the originating exchanger 31 through both of thetrunk connections made to the first terminating exchanger 32 and to thesecond 33. Then, the originating exchanger 31 selects one trunkconnection of the two that is made to the exchanger 32 or 33 thatresponded first to the ISUP requests of the steps S805-1 and S805-2, anddelivers an RBT replacing sound received through the selected trunkconnection to the caller (S809).

If the called answers paging of either of both terminating exchangers 32and 33 (S810) while the determined RBT-replacing sound is beingtransmitted instead of a conventional RBT, the originating exchanger 31,that is informed of the call answer by either exchanger 32 or 33,requests the other exchanger, whose paging is not answered, to releasethe established trunk connection (S811). In this embodiment, it isassumed that the called answers the call paging from the firstterminating exchanger 32, so that the trunk connection made to the firstterminating exchanger 32 is maintained while the other trunk connectionto the second exchanger 33 is released.

Afterwards, the first terminating exchanger 32, based on the callanswer, requests the sound storager 50 to release the established trunkconnection (SB12-1) and the second terminating exchanger 33, based onthe request of ISUP release from the originating exchanger 31, requeststhe sound storager 50 to release the established trunk connection(S812-2). At the same time, voice or data are communicated between thecaller and the called through the trunk connection between theoriginating 31 and the first terminating exchanger 32 (S813).

Another embodiment of the present invention to conduct asubscriber-based RBT-replacing sound providing service after completionof the procedure of FIG. 4 and/or 5 is described. For this embodiment,the steps S406 to S410 in the RBT replacement service subscribingprocedure of FIG. 4 have been conducted.

In this embodiment, the first terminating exchanger 32 and the second 33have received RBT service-related information, which includes the firstinformation on whether RBT is to be replaced or not and the secondinformation informing a route to a corresponding sound storager, when asubscriber's location is registered to the HLR 10 through the firstexchanger 32. Therefore, the above-explained steps to be conducted onand after request of a trunk connection to the sound storager 50 can beapplied to this embodiment as they are.

In all the above-explained embodiments to providing RBT-replacingservice, a subscriber can access the HLR 10 to change the SRBT field ofthe value-added service parameters that pertains to the RBTservice-related information.

For instance, when a subscriber presses a special key on his or hermobile telephone the pressed key information is delivered to the HLR 10which changes the 2-bit SRBT field based on the key information oralternately. However, more significant bit of the two can not be alteredbecause it indicates whether or not subscribed to the RBT replacementservice. Less significant bit can be altered by the above way because itindicates whether the RBT replacement service is activated or not.

Thus, in case of a person having subscribed to RBT replacement service,The SRBT field of the value-added service parameters for that person hasa value: of ‘10’ or ‘11’ only where the value ‘10’ is indicative of‘inactive’ of the service and ‘11’ indicative of ‘active’.

The special key commands change the ‘SRBT’ field from ‘10’ to ‘11’ orfrom ‘11’ to ‘10’. Consequently, a subscriber can determine at willwhether to use a conventional RBT or RBT-replacing sound he or she haschosen. If the ‘SRBT’ field is ‘10’, a terminating exchanger transmits aconventional RBT to a caller even if a called has subscribed to the RBTreplacement service.

While the invention has been disclosed with respect to a limited numberof embodiments, those skilled in the art, having the benefit of thisdisclosure, will appreciate numerous modifications and variationstherefrom. It is intended that the appended claims cover all suchmodifications and variations as fall within the true spirit and scope ofthe invention.

1. A method of providing an arbitrary sound as an RBT (RingBack Tone) ina communication network where flexible paging is conducted for a calledterminal, comprising: a first step, conducted respectively by bothexchangers, of checking whether first information on replacing RBT ornot and second information informing a route to a sound providing meanshas been stored for the called terminal, when an originating exchangerrequests a trunk connection to said both exchangers according to aflexible paging procedure, and receiving the first and the secondinformation from an HLR (Home Location Register) after requesting ifsaid information has not been stored, and requesting a trunk connectionto the sound providing means while furnishing information identifyingthe called, based on the already-stored or the received first and thesecond information; a second step, conducted by the sound providingmeans, of determining an RBT-replacing sound based on thecalled-identifying information, and transmitting the determinedRBT-replacing sound to the originating exchanger through two paths maderespectively by way of said both exchangers; and a third step, conductedby the originating exchanger, of selecting one path of the two, anddelivering the determined RBT replacing sound received through theselected path to a caller.
 2. The method of claim 1, wherein theoriginating exchanger selects one path of the two that is connected toone of said both exchangers that responded first to the trunk connectionrequest of the originating exchanger.
 3. The method of claim 1, whereinsaid both exchangers conduct paging of the called terminal individually,and the originating exchanger maintains the trunk connection made to oneof said both exchangers whose paging is accepted first by the calledterminal and releases remaining trunk connection to the other exchanger.4. The method of claim 1, wherein each of said both exchangers requestsrelease of the trunk connection made to the sound providing means when acall is answered by the called terminal and the sound providing meansreleases the trunk connection in response to each of the releaserequests.
 5. The method of claim 1, wherein the sound providing meansdetermines the RBT-replacing sound specified for the called throughcommunication with a storager controller operating based on internetprotocol.
 6. The method of claim 5, wherein the storager controllerchanges a sound code of an RBT-replacing sound specified for the calledwith another code through communication with a web server operatingbased on internet protocol.
 7. The method of claim 6, wherein saidanother code is a code related with already stored RBT-replacing soundin the sound providing means or is a newly-assigned code for newlystored sound after received from the web server.
 8. The method of claim7, wherein, after being connected to the sound providing means and thestorager controller, the web server changes the RBT-replacing soundbased on subscriber identifying information entered through an input webpage.
 9. The method of claim 1, wherein the first information is setbased a special key information received from the called terminal. 10.The method of claim 1, wherein the first and the second information areincluded in a response message to a location registration requestmessage, the response message being sent from the HLR to thecall-terminating exchangers.
 11. The method of claim 1, wherein thefirst information is written in a reserve field allocated in value-addedservice parameters of subscriber's profile.
 12. The method of claim 1,wherein a message to request the trunk connection to the sound providingmeans from both exchangers further includes information identifying thecaller.
 13. The method of claim 12, wherein the information identifyingthe called and the caller is telephone numbers of the called and thecaller, respectively.
 14. A method of processing location registrationin an HLR (Home Location Register) to provide an arbitrary sound as anRBT (RingBack Tone) in a communication network where flexible paging isconducted for a called terminal, comprising the steps of: furnishing afirst exchanger with first information on whether or not RBT is to bereplaced for a terminal and second information informing a route to asound providing means, when location of the terminal is registeredthrough the first exchanger, and retaining a second exchanger asprevious location of the terminal, the second exchanger having servedthe terminal before; requesting routing information to the first and thesecond exchanger based on the registered and the retained locationinformation of the terminal when location request for the terminal isreceived from an originating exchanger, and providing the first and thesecond information for the second exchanger; and delivering all ofrouting information received, in response to the routing informationrequest, from the first and the second exchanger to the originatingexchanger as a response to the location request.
 15. A method ofprocessing location registration in an HLR (Home Location Register) toprovide an arbitrary sound as an RBT (RingBack Tone) in a communicationnetwork where flexible paging is conducted for a called terminal,comprising the steps of: retaining a second exchanger as previouslocation of a terminal when location of the terminal is registeredthrough a first exchanger, the second exchanger having served theterminal before; requesting routing information to the first and thesecond exchanger based on the registered and the retained locationinformation of the terminal when a location request for the terminal isreceived from an originating exchanger, and providing both of the firstand the second exchanger with first information on whether or not an RBTis to be replaced for the terminal and second information informing aroute to a sound providing means; and delivering all of routinginformation received, in response to the routing information request,from the first and the second exchangers to the originating exchanger asa response to the location request.
 16. A method of providing anarbitrary sound as an RBT (RingBack Tone) in a communication networkwhere flexible paging is conducted for a called terminal, comprising: afirst step, conducted by an HLR (Home Location Register), of furnishinga first exchanger and a second one with first information on whether ornot an RBT is to be replaced for a terminal and second informationinforming a route to a sound providing means, when location of theterminal is registered through the first exchanger, wherein the secondexchanger is registered as previous location of the terminal; a secondstep, conducted respectively by the first and the second exchanger whichare individually requested by an originating exchanger to make a trunkconnection to the originating exchanger according to a flexible pagingprocedure, of requesting the sound providing means to make a trunkconnection therebetween while furnishing information identifying theterminal, based on the first and the second information furnished fromthe HLR; a third step, conducted by the sound providing means, ofdetermining an RBT-replacing sound based on the terminal-identifyinginformation, and transmitting the determined RBT-replacing sound to theoriginating exchanger through two paths made respectively by way of saidboth exchangers; and a fourth step, conducted by the originatingexchanger, of selecting the path of the two, and delivering thedetermined RBT replacing sound received through the selected path to asubscriber who calls the terminal.